One of the most important problems in the field of agricultural activities is water scarcity or water resources issues. In this context, only those countries that utilize scientific methods in supplying the water needed for crops have been able to overcome these problems. In this study, we tried to evaluate the application of meteorological studies in estimating the water requirements of the desired crops (wheat and potato) in Tabriz region during different stages of growth. For this purpose, the ETP (plant evapotranspiration potential) was first determined using long-term statistics, and then, using the FAO organization tables, the plant coefficients for each of the crops were extracted. Finally, in order to plan for the supply of water resources, the effective rainfall in the region has been studied, and by subtracting the amount of water required from effective rain, the amount of water deficiency in the region has been identified.